Many computing systems can present information to a user by displaying text on a screen or some other media, such as a printed page. The physical characteristics of the human visual system and the various types and qualities of electronic display or print technology offer unique challenges to a type designer when developing typefaces in which the text can be presented.
In typography, a typeface consists of a coordinated set of character designs. A typeface is usually comprised of an alphabet of letters, numerals, punctuation marks, ideograms, and symbols (collectively referred to as characters or glyphs). Arial, Times New Roman, Verdana, and Georgia are four examples of typefaces. Traditionally, the word “font” denotes a complete typeface in a particular size (usually measured in points), weight (e.g., light, book, bold, black), and orientation (e.g., roman, italic, oblique). For a given typeface, each character typically corresponds to a single glyph, although certain characters of some typefaces may include multiple glyphs.
Strokes are prominent features of many glyphs. For example, a glyph representing the character ‘E’ may be said to include three horizontal strokes (also called “crossbars”) and one vertical stroke.
In many typefaces, individual strokes may have different relative thicknesses or weights. A relationship of stroke weights is referred to as “stroke contrast”. Stroke contrast can contribute to the readability and aesthetics of a typeface. One challenge to modem type designers is displaying a glyph of a given typeface in such as way as to best preserve stroke contrast for a range of font sizes and display resolutions.